Vertically draining artificial turfs, commonly called “infilled turf”, and as embodied in U.S. Pat. Nos. 4,337,283 and 5,976,645 and others, represent a great improvement over the original short-pile artificial playing surfaces in that they reduce abrasiveness, increase shock attenuation, improve response to foot and ball actions, and have an improved appearance.
Because these turf systems drain vertically, it was necessary to construct a vertically draining stone base, which could infiltrate water from the surface at a rate greater than the rainfall rate expected in a large rainstorm. To accomplish this, it was necessary to build the base with a high infiltration rate. However, such base was less stable, especially with regard to maintaining the high tolerance finish grade, throughout the life out of the turf. As a result, either the infiltration rate or stability of the stone base was composed.
For those reasons, there is a need for constructing artificial turfs that allow rainwater to evacuate at sufficiently large capacity without compromising the structure of the base.